Inflatable surgical cast

ABSTRACT

A water-impervious cast having a rigid tubular outer wall or shell and a flexible tubular inner wall which form a substantially cylindrical chamber about a body portion, such as a leg, arm, torso and the like, to be immobilized by the cast and a foamed-in-place rigid plastic filling the chamber and causing the inner surfaces of the flexible wall to contact the body portion and assume the configuration of the body portion to hold immobile the body portion. A method of forming a cast about a body portion by forming a substantially cylindrical chamber about a body portion by forming a substantially cylindrical chamber about a body portion closed at both ends and having an inner flexible wall movable into engagement with the body portion and introducing a foam-producing substance into the cylindrical chamber to cause it to foam and expand and move the flexible wall into engagement with and to conform to the shape of the body portion while the body portion is immobile.

Young et al.

[ 1 Feb. 22, 1972 [54] INFLATABLE SURGICAL CAST [72] Inventors: JosephV. Young, Route 2, Box 90A,

Lewisville, Tex. 75064; Richard M. Johnson, 3815 Weebum Drive, Dallas,Tex. 75229 [22] Filed: June 16, 1969 [21] Appl. No.: 833,355

[52] US. Cl ..128/90, 128/91 A, 128/DIG. 2O [51] Int.Cl. ..A6lf 5/04[58] Field of Search ..128/90, 87, 89, 83, 83.5, DIG. 20; 3/19, 20

[56] References Cited UNITED STATES PATENTS 2,947,307 8/1960 I-Ioppe..128/90 3,085,569 4/1963 Cook et al.... .128/83.5 X 3,307,537 3/1967Simon et al. ..128/90 3,309,714 3/1967 Porten ..3/20 3,373,741 3/1968Hill et al... ....128/90 3,403,676 10/1968 Gibbons ..128/87 FOREIGNPATENTS OR APPLICATIONS 590,333 l/l960 Canada ..128/90 PrimaryExaminer-Richard A. Gaudet Assistant Examiner-J. Yasko AttorneyWalter J.Jagmln ABSTRACT A water-impervious cast having a rigid tubular outerwall or shell and a flexible tubular inner wall which form asubstantially cylindrical chamber about a body portion, such as a leg,arm, torso and the like, to be immobilized by the cast and afoamed-in-place rigid plastic filling the chamber and causing the innersurfaces of the flexible wall to contact the body portion and assume theconfiguration of the body portion to hold immobile the body portion. Amethod of forming a cast about a body portion by forming a substantiallycylindrical chamber about a body portion by forming a substantiallycylindrical chamber about a body portion closed at both ends and havingan inner flexible wall movable into engagement with the body portion andintroducing a foam-producing substance into the cylindrical chamber tocause it to foam and expand and move the flexible wall into engagementwith and to conform to the shape of the body portion while the bodyportion is immobile.

10 Claims, 7 Drawing Figures PATENTEDFB22 m2 SHEET 2 BF 3 INVENTORSRichard Mdohnson BY Joseph V. Young ATTORNEY PAIENIEUFEB22 m2 3,643,656

SHEET 3 OF 3 R- h m or o nson Fug-7 BY Joseph V; Young WWW A'ITORN E YINFLATABLE SURGICAL CAST This invention relates to casts forimmobilizing body portions.

An object of this invention is to provide a new and improved cast whichcan be easily and quickly disposed about a body portion to immobilizethe body portion.

Another object is to provide a cast which is of relatively greatstrength, but light in weight.

Still another object is to provide a cast, but whose inner surfaceconforms exactly to the contours or configuration of the body portionwhich it encloses.

A further object is to provide a cast which permits circulation offluids, such as air or liquids, about the body portion enclosed thereby.

An important object is to provide a cast which has an outer rigidsubstantially cylindrical shell or wall formed of two connectablesections in which a body portion such as a leg, arm or the like, may bepositioned, the shell having such internal configuration atsubstantially all locations 'as to permit the outer shell to be spacedfrom and out of contact with the body por- 'tion, an internal wallformed of a flexible means which is movable inwardly into engagementwith the body portion and connectable at its opposite ends to. the outershell to form therewith a substantially cylindrical chamber, and afoamedin-place substance filling the cylindrical chamber and causing theinner flexible means to conform to the shape of the body portionpositioned in the case and engage the body portion.

Another object is to provide a cast wherein a flexible cutting member asdisposed within the cast and is usable to cut through the cast when itis desired to remove the cast.

Still another object is to provide a cast formed of a substance whichpermits the X-raying of the body portion while the cast is in place onthe body portion.

Still another object is to provide a cast wherein the inner wall isformed of a resilient open-celled or porous substance to permitcirculation of fluids about the body portion in the cast.

Additional objects and advantages of the invention will be readilyapparent from the reading of the following description of a deviceconstructed in accordance with the invention, and reference to theaccompanying drawings thereof, wherein:

FIG. 1 is a side view of a cast embodying the invention adapted for useon a leg and showing the cast in place on the leg;

FIG. 2 is a sectional view taken on line 22 of FIG. 1, the thicknessesof the components forming the inner flexible wall being exaggerated forclarity of illustration;

FIG. 3 is a sectional view taken on line 3-3 of FIG. 2, the thicknessesof the components forming the inner flexible wall being exaggerated forclarity of illustration;

FIG. 4 is a perspective exploded view of all components of the castexcept the foamed-in-place plastic substance;

FIG. 5 is a perspective view of the flexible inner wall;

FIG. 6 is a fragmentary enlarged perspective view showing the manner inwhich a cast-cutting wire is connected to a heelpiece of the cast; and,

FIG. 7 is a view of a cast embodying the invention adapted for use onthe forearm and showing the cast in place on the forearm.

Referring now to FIGS. 1 through 6 of the drawings, the cast 10embodying the invention for use on the leg and foot includes a rigidouter wall or shell 11 formed of two sections 12 and 13. The rear shellsection 12 has a substantially semicylindrical wall 14 which is providedat its bottom end with a downward protuberance 15 provided with anaperture 16 in which is receivable the lug 17 of a heelpiece 18. Theheelpiece may be formed of a somewhat resilient plastic substancereinforced by a metal reinforcing member 19 embedded therein.

The left edge of the wall 14 of the shell is provided with an outwardlyextending flange 20 and similarly the right edge of the cylindrical wallis provided with an outwardly extending flange 21. The bottom ends ofthe flanges 20 and 21 are spaced to provide a downwardly opening slot 22for a purpose to be described.

The front shell section 13 similarly has a cylindrical wall 25 and atubular foot-receiving portion 26. The left-hand edge of the cylindricalwall has an outwardly extending flange 27 and its right-hand edge has anoutwardly extending flange 28. The bottom portion of the front shellsection is provided with a downward protuberance 29a having an aperture30 in which is receivable the front lug 32 of the heelpiece 18. Thelowermost substantially horizontally extending portions of the edgeflanges of the two shell sections are receivable in the verticalupwardly opening recess 33 of the heelpiece. The bottom ends of theflanges 27, and 28 are spaced to provide a downwardly opening slot 29which is aligned with the slot 22 when the heelpiece is positioned onthe two shell sections with its lugs extending through the apertures 16and 30.

The two shell sections 12 and 13 may be secured to one another by anysuitable means such as a strip of adhesive tape or by clamp strips 34and 35 which are adapted to resiliently extend about the aligned flanges20 and 27, and 21 and 28, respectively, of the two shell sections. Thetwo shell sections are also held together by the heelpiece 18 since thelower ends of the flanges of the two shell sections are received in thegroove or recess 33 of the heelpiece and the lugs 17 and 32 of theheelpiece are received in the apertures 16 and 30 of the sections 12 and13, respectively.

The two shell sections are formed of a rigid plastic substance, such asacrylonitrile-butadiene-styrene, polycarbonate or high-impactpolystyrene, which is relatively lightweigt, water impervious andstrong.

The cast includes an inner substantially tubular flexible wall 40comprising two sheet sections 41 and 42 formed of an open-cell foamsubstance, such as polyurethane commercially available under the markScott Foam" which because of its open-cell structure permits passage offluids therethrough. For example, the sheets may be one-eighth inchthick and have pores per linear inch.

The wall section 41 has a longitudinal body portion 43 provided at itsupper end with the oppositely extending tabs 44 and 45 and a footportion 47 which extends angularly from the lower end'of theperpendicular portion and is provided with oppositely extending tabs 48and 49 at its outer end portion.

The wall section 41 also has a downwardly extending tab 51 which isadapted to extend downwardly (see FIG. 3) through the aperture providedby the aligned slots 22 and 29 of the shell sections 12 and 13,respectively. The inner surfaces of the inner wall section 41 areprovided with layers 54 and 55 of a suitable pressure-sensitive adhesiveso that the sections 4] and 42 may be secured to one another along theiropposite side portions.

The inner wall section 42 being identical in structure to the inner wallsection 41, its various portions have been provided with the samereference numerals, to which a subscript a," has been added as thecorresponding portions of the inner wall portion 41.

A cutter or cast stripper member 57 is secured to the inner surfaces ofthe inner wall sections 41 and 42 by means of ad hesive strips 58 and580, respectively. The cutting member 57 may be a stainless steel cable.The middle portion of the cutting member 57 extends downwardly of thelower ends of the bottom tabs 51 and 51a and is formed into a loop whichis positionable about the lug 32 of the heelpiece. The opposite endportions 59 and 59a of the cutter member extend outwardly throughapertures in the inner wall portions 41 and 42, respectively, and may beformed into loops as is illustrated in FIGS. 1,3 and 5.

The inner wall may also include a sheet 62 of a plastic substance, suchas is commercially available under the name Saran Wrap," which may bewrapped about the sections 41 and 42 after they have been placed aboutthe leg of the wearer. Alternatively, the sheet 62 may be in the form oftwo sections, not shown, of the same configurations as the sections 41and 42 and be bonded thereto prior to the placement of the sections 41and 42 about the leg. The impermeable sheet 62 is used to prevent afoaming liquid, as will be explained below, from coming into contactwith the leg of the wearer.

The cast may include, FIG. 3 and 4, a heel support or block 64 which maybe used to hold the heel and the rear outer wall shell section 12 inproper spaced relation to the leg of the wearer during the forming ofthe cast. The heel support may be made of polyurethane foam.

In use, a woven stocking 65 may be placed about the foot and lower legof the leg which is to be immobilized by the cast 10. The rear layers 55of adhesive on the inner surfaces of the two sections then secure therear and bottom portions of the inner wall sections 41 and 42 to oneanother and these two sections are then placed about the leg. Theforward portions of the sheets are then secured to one another by thefront layers 54 of adhesive on the inner surfaces, as illustrated inFIG. 5. The impermeable sheet 62 is then wrapped about the inner wallsections 41 and 42 to form a liquidtight covering therefor with thesections 41 and 42 held in somewhat loose engagement with the leg andfoot. If the sheet is in the form of two sections bonded to the sections41 and 42, the impermeable sheet obviously is disposed about the leg atthe same time as the sections 41 and 42. The sheet 62 is wrapped aroundthe tabs 51 and 51a or is perforated to permit them to pass downwardlythereof. The two tabs 51 and 51a which are now secured to one another,as illustrated in FIG. 6 and extend downwardly through the apertureformed by the aligned slots 22 and 30 of the shell sections 12 and 13 ofthe outer wall.

The rear shell section 12 is then disposed as illustrated in FIG. 3,about the rear portions'of the leg, heel and foot of the wearer whilethe heel support prevents the heel from engaging the rear shell section12. The bottom edges of the flanges and 21 are inserted in the recess 33of the heel while the heelpiece lug 17 is positioned in the aperture 16.

The middle loop portion 58 of the cutting member is disposed about thelug 32 of the heelpiece and the front shell portion 13 is placed overthe foot of the wearer and the bottom portions of its flanges 27 and 28are inserted into the recess 33 of the heelpiece. The lug 32 is receivedin the aperture 30.

The loop 58 as illustrated in FIGS. 3 and 6 is then held againstdisplacement oh" the heelpiece lug 32 by the bottom inner portion of thefront shell section 13.

The two rigid shell sections 12 and 13 are then secured to one anotherby the clamp strips 34 and 35 or alternatively by surgical adhesive tapeand the like.

The upper portions of the tubular inner wall formed by the inner wallsections 41 and 42 defined by the broken lines 66 and 67, FIG. 5, whichnow extend upwardly of the top edges of semicylindrical wall portions 14and of the shell sections 12 and 13, respectively, are folded downwardlyover the shell sections as illustrated in FIGS. 1 and 3. A strip ofadhesive tape 69 is then wrapped about the folded-down portions andlapped over the shell sections to secure the folded-down portions to theshell sections and close the upper end of the chamber 70 formed by andbetween the inner and outer walls.

The portions of the inner wall sections 41 and 42 extending forwardly ofthe lines 72 and 73 extend forwardly of the front edge of the tubularfoot portion 26 of the shell section 13 and are similarly folded backthereon, as illustrated in FIG. 3, to close the bottom end of thetubular chamber and secured to the foot portion by an adhesive tape 74.

The leg is then supported in a horizontal position and a liquid mixtureof polyurethane, freon and a catalyst, the freon being in solution inthe polyurethane or the catalyst, is poured in the chamber 70 through anaperture 75 in the front shell section in sufficient quantity that asthe freon vaporizes, the freon-blown polyurethane foam 76 will fill thetubular chamber and cause the flexible inner wall to move inwardly atall locations therealong to expand the tubular chamber and to conform tothe shape of the leg and foot. When the chamber is fully expanded anyexcess foam produced therein will flow out through the aperture 75 sothat the body portion is not compressed or placed under pressure at anylocation. The foamedin-place polyurethane forms a rigid closed-cell foamwhen it sets or hardens.

The leg is now held notionless relative to the outer wall for a periodof time which is relatively short, for example, approximately 5 minutes,until the substance 76 hardens or sets. The polyurethane bonds to theshell sections 12 and 15 and to the inner wall sections 41 and 42 as ithardens.

The inner surfaces of the cast now conform exactly to the configurationof the leg and foot enclosed by the cast and, at the same time,immobilize the leg.

The thickness of the inner wall sections 41 and 42 and of theimpermeable sheet 62 have been exaggerated in FIGS. 2 and 3 for clarityof presentation. The inner wall sections may, for example, be one-eighthof an inch thick while the sheet 62 may be five ten-thousandths of aninch thick.

The stocking 65 .and the inner wall sections 41 and 42, which are of anopen-cell foam substance, permit air to circulate to some extent throughthe cast and about the leg encased thereby. In addition, if desired,liquids may be allowed to flow through the cast and about the legthrough the inner wall sections 41 and 42 and the stocking 65 to washthe leg or to apply medications thereto. The foam substance 76, however,which fills the chamber is not permeable to liquids.

Since the substance 76 and the shell sections 41 and 42 are not liquidpermeable, even if the cast is submerged in a liquid, no appreciableamount of liquid will be absorbed thereby. In addition, the varioussubstances of which the various components of the cast are formed arenot water soluble so that the cast may be washed and desired liquidscirculated through the cast and about the leg.

It will now be seen that the cast 10 embodying the invention comprises atubular chamber means formed, for example, of the two inner wallsections 41 and 42 and the outer wall shell sections 12'and 13 whichprovides a substantially cylindrical chamber which is closed at bothends.

It will further be seen that the chamber means includes a nonexpansibleouter wall formed by the rigid channel members 12 and 13 and a flexibleinner wall, formed of the inner wall sections 41 and 42, which ismovable inwardly toward the body portion until its inward movement islimited by the body portion which the cast encloses and the inner wallconforms to the configuration of the body portion.

It will further be seen that the inner wall is moved inwardly to engageand to conform to the outer surfaces of the body portion when a liquidis introduced into such chamber and such liquid foams and expands tofill such tubular chamber and move the inner wall sections inwardly.

It will also be seen that the flexible inner wall may include aliquid-impermeable sheet 62 disposed about the inner wall sections 41and 43 to prevent the liquid introduced into the chamber from contactingthe leg itself.

It will further be seen that the method of making a cast on a bodyportion, such as a leg, includes disposing a substantially tubularchamber means formed of such elements as the outer wall and the innerflexible wall 40, and introducing a foamforming liquid into the chamberto fill the chamber and cause the inner wall to move inwardly until itsinward movement is limited by the body portion, and holding the cast andthe body portion against movement relative to one another until theproduced foam hardens or becomes rigid.

It will be apparent that the cast is of very lightweight and that it maybe washed or subjected to liquids unlike the usual heavyliquid-absorbing and liquid-soluble plaster cast, and that is permitsflow of liquids between the leg and the cast which may be desired ifmedication or washing of the skin is required or desirable.

The foregoing description of the invention is explanatory only, andchanges in the details of the construction illustrated may be made bythose skilled in the art, within the scope of the appended claims,without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent 1. A castfor immobilizing a body portion. said cast including: chamber meanspositionable about a body portion providing a substantially cylindricalchamber closed at both ends, said chamber means including anonexpansible substantially tubular outer wall and an inner flexiblewall adapted to move inwardly and away from said outer wall until itsinward movement is limited by a body ponion about which said means isdisposed and to conform to the configuration of the body portion, saidouter wall having an open aperture; and a rigid foamed-in-placeclosed-cell substance introduced in fluid state into the chamber throughsaid aperture filling said chamber and holding said inner wall againstoutward movement, said inner wall means comprising a sheet of open-cellfoam substance and a sheet of liquid-impermeable substance disposedabout said sheet of open-cell foam substance, said outer wall meanscomprising a pair of opposed substantially semicylindrical rigidsections and means for rigidly securing said sections to one another.

2. The cast of claim 1, and flexible cutter means disposed within saidinner wall means and having opposite end portions extending outwardly ofsaid cast.

3. The cast of claim 2, wherein said outer wall sections are providedwith external flanges, said cutter means being movable between saidflanges to cut through said inner wall means and said rigid foramsubstance to permit removal of said cast from a body portion.

4. The cast of claim 1, wherein said shell sections are adapted to bedisposed about a leg and foot to be immobilized, the outer of said shellsections having a tubular foot-receiving portion, said inner wall meansextending through said tubular foot portion of said front shell sectionand being secured thereto.

.5. The cast of claim 4, and a heelpiece rigidly secured to said shellsections.

6. The cast of claim 5, wherein said heelpiece is provided with atransversely extending groove, said shell sections having edge flanges,said flanges of said shell sections being received in said groove.

7. The cast of claim 6, wherein said heelpiece is provided with a pairof upwardly extending lugs and said shell sections are providedwithapertures in which said lugs are received.

8. The cast of claim 7, and a flexible cutter member disposed inwardlyof said inner wall and having a middle loop portion disposed about oneof said lugs and between said heelpiece and the bottom end of one ofsaid shell sections.

9. The cast of claim 8, wherein said inner wall sections are of opencell polyurethane foam substance.

10. The cast of claim 9, wherein said foam substance in said chamber isa low-density, freon-blown polyurethrane. polyurethane.

IIHIIA hill

1. A cast for immobilizing a body portion, said cast including: chambermeans positionable about a body portion providing a substantiallycylindrical chamber closed at both ends, said chamber means including anonexpansible substantially tubular outer wall and an inner flexiblewall adapted to move inwardly and away from said outer wall until itsinward movement is limited by a body portion about which said means isdisposed and to conform to the configuration of the body portion, saidouter wall having an open aperture; and a rigid foamed-in-placeclosedcell substance introduced in fluid state into the chamber throughsaid aperture filling said chamber and holding said inner wall againstoutward movement, said inner wall means comprising a sheet of open-cellfoam substance and a sheet of liquidimpermeable substance disposed aboutsaid sheet of open-cell foam substance, said outer wall means comprisinga pair of opposed substantially semicylindrical rigid sections and meansfor rigidly securing said sections to one another.
 2. The cast of claim1, and flexible cutter means disposed within said inner wall means andhaving opposite end portions extending outwardly of said cast.
 3. Thecast of claim 2, wherein said outer wall sections are provided withexternal flanges, said cutter means being movable between said flangesto cut through said inner wall means and said rigid foram substance topermit removal of said cast from a body portion.
 4. The cast of claim 1,wherein said shell sections are adapted to be disposed about a leg andfoot to be immobilized, the outer of said shell sections having atubular foot-receiving portion, said inner wall means extendinG throughsaid tubular foot portion of said front shell section and being securedthereto.
 5. The cast of claim 4, and a heelpiece rigidly secured to saidshell sections.
 6. The cast of claim 5, wherein said heelpiece isprovided with a transversely extending groove, said shell sectionshaving edge flanges, said flanges of said shell sections being receivedin said groove.
 7. The cast of claim 6, wherein said heelpiece isprovided with a pair of upwardly extending lugs and said shell sectionsare provided with apertures in which said lugs are received.
 8. The castof claim 7, and a flexible cutter member disposed inwardly of said innerwall and having a middle loop portion disposed about one of said lugsand between said heelpiece and the bottom end of one of said shellsections.
 9. The cast of claim 8, wherein said inner wall sections areof open cell polyurethane foam substance.
 10. The cast of claim 9,wherein said foam substance in said chamber is a low-density,freon-blown polyurethrane. polyurethane.